This invention relates to stackable containers and, more particularly, stackable containers formed from pre-cut and pre-scored unitary blanks.
Typically, containers utilized in the storage, shipping, and display of produce, nuts, fruits, and the like are formed from unitary blanks. A unitary blank is formed by cutting and scoring a single sheet of corrugated paperboard or a similar material, i.e., a starting sheet, with a predetermined pattern to enable the blank to be folded to form a container. In use, the containers are loaded with the selected product and are stacked upon each other. Thus, it is advantageous for such containers to be securely stackable. However, difficulties can arise in stacking several fully-loaded containers. For example, the accumulated weight may cause damage to containers at the bottom of the stack, such as, collapsing a corner. Also, the containers may not properly align causing the stack to bias in a particular direction and potentially to fall over. A variety of stackable containers are known in the art, incorporating stacking tabs and reinforcing structures. Yet, many containers incorporating such features are relatively difficult to construct, requiring several steps to fully assemble.
In many applications for stackable containers, it is customary for such containers to be manufactured in one located and assembled in another. Thus, it is further advantageous for such containers to assemble easily. Furthermore, such containers do not optimize the use of materials, and some stackable containers require the integration of several blanks for full assembly, rather than attaining the benefits of unitary blank assembly.
It should, therefore, be appreciated there is a need of an improved container formed of a unitary blank having reinforced corners and stacking tabs with improved stacking strength and stability, which employs efficient usage of sheet material and assembles with relative ease while improving cost-effectiveness. The present invention fulfills this need and others.
The present invention is embodied in a stackable container utilized in the storage, shipping, and display of produce, nuts, fruits, and the like, formed from a unitary blank pre-cut and pre-scored with an improved design in which, once assembled, the container has enhanced stacking and strength attributes. Moreover, the improved design is such that more efficient use of the material is made. More particularly, the container includes a base with two sets of opposing walls. The first set of walls each include a first panel attached at a lower edge to the base and a second panel attached at an upper edge to the first panel and thereby forming at least one stacking tab having a two-ply thickness. The second set of opposing walls each include an outer panel attached to the base; two center flaps, each attached to the corresponding side edge of the first panel thereby forming a corner; and two inner flaps, each attached the corresponding center flap. The container further includes four reinforcement panels, each attached to the adjacent side edge of the corresponding second panel.
In a detailed aspect of a preferred embodiment of the invention, the side the second panels of the first set of walls are sized such that their side edges are positioned a selected distance away from the corner, and thereby the reinforcement panels are oriented in a triangular configuration with respect to the corresponding corners.
In another detailed aspect of a preferred embodiment of the invention, each inner flap is positioned a selected distance from the corresponding corner and the terminal edge of the corresponding reinforcement panel abuts the first side edge of the inner flap such that it locks in place.